Fuel-burner for cement-kilns.



ATTORNEY M. F. MANGELSDORFP. FUEL BURNER FOR CEMENT KILNS. APPLIOATION FILED APR. 7, 1906.

Patented Nov. 29, 1910.

52: ffl X IIVVEIVTUR v A By WITNESSES.

. UNITED STATES PATENT, o nnion.

MAXI. menennsnonnr, on NEW YORK, n. Y., assmnon. 'ro COMBUSTION UTILITIES COMPANY, onnnw YORK, N. Y., A conrona'rron or'nnw YORK.

FUEL-BURNER. non GEMENT-KILNS.

Specification of Letters'ratent. Patented Nov. 29, 1 910;.v

Application filed ApriI 7, 1906. Serial No. 310,574.

To all whom it may concern."

Be it knownthat I, MAX nonrr, a citizen of the United States, and resident of New York, in the county of New York and State of New York, have invented a certain new and useful Fuel-Burner for Cement-Kilns, of which the following is a specification. k

This invention relates to fuel burners for cement kilns and consists in a device for injecting powdered fuel with air and feeding auxiliary air to the jet so formed in order to produce a positive, regulable flame suitable for heating rotary cement kilns,.such

as are employed, forburning Portland cement and for like purposes; all as more fully hereinafter set forth and as claimed.

In the modern practice of cement burning the dry material, which is a mixture of clay and limestone, artificially 'or naturally admixed, is progressively advanced through a rotating inclined'kiln, lined with refractory materials, in heating relation to a flame burning in the mouth of the kiln. This il'ime must aflor'd temperature enough to frit' or 'sinter' the clay component of the cement mixture, since otherwise it would not enter into the clinker-making reaction with the lime from the limestone, but it must not injure the refractory material of the lining, which is generally fireclay. It

is obvious that a nice regulation of temperature is requisite to meet these requirements.

Powdered coal burning in aerial suspension is one of the few cheap and available fuels which will yield the necessary temperature for clinker-makin but unfortu natelyit also yields-rather more. making it dangerous to kiln linings unless the flame be under thorough control. It is the purpose of the present invention to provide a powdered coal flame which shall be under such thorough control and-which shall produce asafe but powerful clinkering action.

. In the present practice, it is the custom to injectthe coal dust with only a. few per cent. of the air necessary to burn it, depending upon the draft of the kiln to furnish the residue. There are several reasons for this practice, one being that a mixture of coal dust with the full amount of air ofecourse furnishes an explosive bodyand should the rate of feed through the burnernozzle teniporarily fall below the backward rate of flame propagation, dangerous, explosions F. Miriam might result; another being that a is due- I cult to suspend coal evenly and uniformly throughout such an amount of air, and still a third being that the air currents entering throu h the mouth of the kiln. are relied upon 0 form a relatively cold sheath about the flame, spacing it away from the kiln wallsand material thereon and obviating danger from the unduly hot'flame produced from the ordinary round jet nozzle.v In the present invention, I depart from this prac- Itice and while feeding in the coal dust directly withonly a limited, safe amount of air, I inject into, and carry the flame plume by, the rest of the air in the form of auxiliary 'ets substantially parallel thereto.

In t e accompanying illustration, I have shown certain forms of apparatus within my invention for accomplishing the described objects. In this showings Figure 1 is a plan view of one embodiment 'of my invention; Fig. 2 is an end elevation of the same structure, showing the crosssectional relationship of the elements; Fig. 3 is a plan view of a modification; Fig. 4 is a similar end elevation of the structure of Fig. 3; Fig. 5 is a plan view of another modification; Fig. 6 is an end elevation of Fig. 5; Fig. 'l is a longitudinal elevation of another modification; and Fig. 8 is an end elevation of the same.

Like reference characters are employed for like elements throughout the showing.

The main air supply trunk, 1, is connected with a'suitable source of air, or of air mixed with products of combustion in case it is desirable to temper the coal flame.

2 and 2' are blast nozzles communicating with the air trunk and opening-into the discharge pipes at and 4, directly beneath the hoppers 3 and 3' for powdered fuel. 5

and 5 are auxiliary air pipes also connected to the air trunk,'but unprovld'ed with In Fig. 1, the cha'mber- .has lparallel' or slightly tapering sides and is so constructed as the area of cross-secti'ontifpipes,4,5 and hoppers or nozzles. They discharge air'iii a direction parallel to the discharge from that the open endshal-l'hayethe. same-area .the formation of a flattened flame.

5. This results in the coal-charged air jet! and the other air ets flowing out of the end of the chamber in substantially parallel lines. As the air in 5 and 5" does not pass through a nozzle or carry coal, it will emerge with a greater velocity than that from discharge pipe 4:, other conditions being equal, and will entrain it. As shown, the mixing or nozzle chamber 6 has a flattened opening and will produce a flattened flame of less localized intensity in any one part than will the ordinary round jet nozzle. In Fig. 3, the two outer pipes carry coal while the free air pipe is between them. The burner nozzle, as shown, has a slight out.- ward flare which contributes materially to the figures, the, construction of the burner nozzle is such that the air currents will still preserve substantial parallelism beyond the opening thereof, the s wifter moving air jet helping to carry forward the coal laden jet. In .Fig. 5, the nozzle chamber is provid'ed a constriction 8 which assists in perfecting the contacting of the two classes of jets prior to their emergence from the nozzle.

In Figs. 7 and 8 a similar construction is shown provided with a dead plate 7 in order to provide for a spreading of the flame.

The higher velocity of the air jet causes it to act inductively on the slower moving coal jet, assisting in carrying forward the fuel, and the two together act to form a positive flame, easily directed and shifted and easily controllable as to length and impingement. To produce these results it is substantiallynecessary that the two classes of1 jet should bef ts shown, practically paral el.

What I claim is 1. A flat-flame burner for cement kilns comprising a source of air under pressure, a

flattened nozzle chamber having an unrestricted, full-area flame outlet, a coal-jet conduit connected to said source and ending at and communicating with the nozzle chamber, means for discharging powdered coal into said pipe, and an air conduit, also con- In both 'nected to said source and nected to said source and ending within said chamber, adapted to form an. air jet parallel to and contacting with the air-coal jet coming from the firstnamed conduit, the shape of the nozzle chamber and flame-outlet beingsuch as to produce a flattened flame and maintain the separate existence of the several jets.

2. A flat-flame burner for cement kilns comprising a source of air under pressure, a flattened nozzle chamber having a flattened, unrestricted, full-area flame outlet, a coal-jet conduit connected to said source and ending at and communicating with the nozzle chamber, means for feeding powdered coal into said pipe, and an air conduit, also connected to said source and ending within said chamber, adapted to form an air jet parallel to and contacting with the air-coal jet coming from the first-named conduit, the shape ofsaid nozzle chamber and flame outlet being such as to produce a flattened flame and maintain the separate existence of the several jets.

3. A flat-flame burner for cement kilns comprising a source of air under a nozzle chamber of a flattened shape with a median constriction and having a flat-- pressure,

tened, full-area flame outlet, a coaljet con- I duit tconnected to said source and ending within the nozzle chamber behind said constriction, means for feeding powdered coal into said pipe, and an air conduit, also 0011 ending within the chamber behind the constriction, adapted to form an air jet parallel to and contacting with the air-coal jet coming from the firstnamed conduit, the shape of said, nozzle chamber and flame outlet being such as to produce a flattened flame and maintain the separate existence of the several jets.

Signed at New York in the county of New York and State of New York this 5th day of April A. D. 1906.

MAX F. MANErELSDORFF. 

